This invention is in the field of sewing machine attachments; more particularly, it is concerned with an improved attachment which facilitates needle feed of work material in a sewing machine in which presser foot pressure is normally constant.
In a prior art device, a combination needle feed and even feed attachment is provided which, selectively, implements lateral feeding of a work material by a sewing needle, or longitudinal feeding thereof by means of a work feeding foot which cooperates with motion of the sewing machine feed dog to shift the upper and lower plies of a work material in a longitudinal direction. The combination attachment is supported on a presser bar of a sewing machine. Needle feed is implemented by shifting the presser foot upwardly when the sewing needle is in engagement with a work material so as to reduce the pressure on the work material and to enable ready lateral shifting thereof. The presser foot is carried on one end of a presser foot carrier lever which is pivoted substantially centrally thereof and is fashioned with a gear segment opposite the end supporting the presser foot. A pinion is maintained in mesh with the gear segment and is carried on a pin on the end of a pinion carrier lever pivoted beyond the pinion from the pivot axis of the presser foot carrier lever. A pinion lock is pivoted adjacent the pinion carrier lever and is formed on the opposite end thereof with a tooth or teeth designed for engagement with the pinion to check rotation thereof pursuant to additional pressure on the pinion lock to rotate the presser foot carrier lever and thereby elevate the presser foot out of contact with the work material. Pressure is applied to the pinion lock by a push lever, by means of a roller on a drive lever connected to the reciprocating needle bar to influence rotation thereof, and, thereby, rotation of the presser foot carrier lever, when the sewing needle enters into engagement with a work material.
Such an attachment device has been found to be efficacious for stitching patches to a garment because of its capability for longitudinal and lateral feeding. What is required is an improved needle feed attachment device which is substantially similar to the combined device but eliminates many parts and combines other parts thereof to provide a considerably simplier and more economical assembly.